Technical Field
The invention relates to a display technique, and particularly relates to a display apparatus implementing display by using light-emitting units having different photoelectric conversion efficiencies and covering color gamuts, and a method for controlling a backlight module thereof.
Related Art
A general liquid crystal display (LCD) is mainly composed of a backlight module and a liquid crystal panel. Since the liquid crystal panel itself does not emit light, the backlight module is required to provide a planar light source required for displaying, so as to present image containing various colors.
The LCD installed on a mobile device is portable, and a usage environment thereof is not fixed. For example, when the mobile device is used outdoors or used under a strong sunlight, the user hopes that the LCD on the mobile device is capable of increasing a screen brightness to avoid unclear display of images, and when the user uses the mobile device in a dark environment, the user hopes that the LCD on the mobile device is capable of automatically decreasing a screen brightness to avoid over bright of the screen to hurt user's eyes.
However, generally, the existing display apparatus can only adjust a display brightness of the backlight module, and cannot adjust a display chroma (a display color gamut) of the backlight module. In other words, when the user hopes the screen of the mobile device to be more colourful, the mobile device and the applications installed on the mobile device cannot implement color gamut adjustment by using hardware equipment on the mobile device. Moreover, regarding light-emitting diodes (LEDs) currently used for providing the brightness of the backlight module, limited by a material characteristic, a photoelectric conversion efficiency of the LEDs with larger covering color gamut is lower than a photoelectric conversion efficiency of the LEDs with smaller covering color gamut, and if the light sources of the backlight module are all the LEDs with larger covering color gamut in order to satisfy the user's demand on more colourful screen of the mobile device, power consumption of the light-emitting unit is increased and a usage time of the mobile device is decreased, such that user's requirement for prolonging the usage time of the mobile device cannot be achieved.
Therefore, it is an important issue to ensure the display apparatus to efficiently implement free adjustment on image brightness and color performance under different situations, so as to suitably decease power consumption of the light-emitting unit and hardware cost.
Taiwan Patent Publication No. 201024863 discloses a backlight module having two light-emitting units respectively operated in different color gamuts, where each of the light-emitting units has at least one light-emitting diode, and the two light-emitting units are used in collaboration to achieve a larger color gamut performance of the display apparatus. Taiwan Patent No. M457891 discloses an LED light bar capable of providing a high brightness or a low brightness according to the number of used LEDs. China Patent No. 202206608 discloses an illumination control apparatus capable of automatically adjusting electric energy supplied to a load according to total electric quantity. China Patent No. 203395793 discloses a solar LED street lamp capable of continuously lighting a first LED light source with a lower power, and when a pedestrian comes up, the city power is supplied to a second LED light source for lighting, such that the first LED light source and the second LED light soured simultaneously emit light to improve an illumination brightness.
The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the invention was acknowledged by a person of ordinary skill in the art.